Sign Data Hiding of Video Recording

The present application is a continuation of U.S. application Ser. No. 17/211,340, filed Mar. 24, 2021, which claims the benefit of priority to U.S. Provisional Patent Application No. 62/994,239, filed on Mar. 24, 2020, both of which are incorporated herein by reference in their entireties.

The present disclosure generally relates to video data processing, and more particularly, to residual coding of video data.

A video is a set of static pictures (or “frames”) capturing the visual information. To reduce the storage memory and the transmission bandwidth, a video can be compressed before storage or transmission and decompressed before display. The compression process is usually referred to as encoding and the decompression process is usually referred to as decoding. There are various video coding formats which use standardized video coding technologies, most commonly based on prediction, transform, quantization, entropy coding and in-loop filtering. The video coding standards, such as the High Efficiency Video Coding (e.g., HEVC/H.265) standard, the Versatile Video Coding (e.g., VVC/H.266) standard, and AVS standards, specifying the specific video coding formats, are developed by standardization organizations. With more and more advanced video coding technologies being adopted in the video standards, the coding efficiency of the new video coding standards get higher and higher.

Embodiments of the present disclosure provide a method for video data coding, the method comprises: receiving a video frame for residual coding; determining whether the video frame is coded according to a transform skip mode at a transform block level; and in response to a determination that the video frame is coded according to the transform skip mode, turning off sign data hiding for the residual coding.

Embodiments of the present disclosure further provide a method for video data coding, the method comprises: receiving a video frame for residual coding; determining whether the video frame is coded according to a block differential pulse-code modulation mode; and in response to a determination that the video frame is coded according to the block differential pulse-code modulation code, turning off sign data hiding for the residual coding.

Embodiments of the present disclosure further provide a method for video data coding, the method comprises: receiving a video frame for residual coding; determining whether the video frame is coded according to a transform skip residual coding mode at a slice level; and in response to a determination that the video frame is not coded according to the transform skip residual coding mode at the slice level, turning off sign data hiding for the residual coding.

Embodiments of the present disclosure further provide a method for video data coding, the method comprises: receiving a video frame for residual coding; determining whether sign data hiding is enabled at a picture level for the video frame and whether transform skip residual coding is disabled at a slice level for the video frame; and in response to a determination that the sign data hiding is enabled at the picture level for the video frame and the transform skip residual coding is enabled at the slice level for the video frame, turning on sign data hiding at the slice level for the video frame.

Embodiments of the present disclosure further provide a method for video data coding, the method comprises: receiving a video frame for residual coding; determining whether sign data hiding is enabled at a picture level for the video frame; in response to a determination that the sign data hiding is enabled at the picture level for the video frame, turning on sign data hiding at a slice level for the video frame; determining whether sign data hiding is turned off at the slice level for the video frame; and in response to a determination that the sign data hiding is turned off at the slice level for the video frame, turning off transform skip residual coding at the slice level for the video frame.

Embodiments of the present disclosure further provide a method for video data coding, the method comprises: receiving a video frame for residual coding; determining whether the video frame is coded in a lossless mode at a slice level; and in response to a determination that the video frame is coded in the lossless mode at the slice level, turning off one or more loop filters at the slice level.

Embodiments of the present disclosure further provide a method for video data coding, the method comprises: receiving a video frame for residual coding; determining whether sign data hiding is turned off at a picture level for the video frame; in response to a determination that the sign data hiding is turned off at the picture level for the video frame, turning off transform skip residual coding at a slice level for the video frame.

Embodiments of the present disclosure further provide a method for video data coding, the method comprises: receiving a video frame for residual coding; determining whether a dependent quantization is enabled for the video frame; in response to a determination that the dependent quantization is enabled for the video frame, turning off transform skip residual coding at a slice level for the video frame.

Embodiments of the present disclosure further provide a system for performing video data processing, the system comprising: a memory storing a set of instructions; and a processor configured to execute the set of instructions to cause the system to perform: receiving a video frame for residual coding; determining whether the video frame is coded according to a transform skip mode at a transform block level; and in response to a determination that the video frame is coded according to the transform skip mode, turning off sign data hiding for the residual coding.

Embodiments of the present disclosure further provide a system for performing video data processing, the system comprising: a memory storing a set of instructions; and a processor configured to execute the set of instructions to cause the system to perform: receiving a video frame for residual coding; determining whether the video frame is coded according to a block differential pulse-code modulation mode; and in response to a determination that the video frame is coded according to the block differential pulse-code modulation code, turning off sign data hiding for the residual coding.

Embodiments of the present disclosure further provide a system for performing video data processing, the system comprising: a memory storing a set of instructions; and a processor configured to execute the set of instructions to cause the system to perform: receiving a video frame for residual coding; determining whether the video frame is coded according to a transform skip residual coding mode at a slice level; and in response to a determination that the video frame is not coded according to the transform skip residual coding mode at the slice level, turning off sign data hiding for the residual coding.

Embodiments of the present disclosure further provide a system for performing video data processing, the system comprising: a memory storing a set of instructions; and a processor configured to execute the set of instructions to cause the system to perform: receiving a video frame for residual coding; determining whether sign data hiding is enabled at a picture level for the video frame and whether transform skip residual coding is disabled at a slice level for the video frame; and in response to a determination that the sign data hiding is enabled at the picture level for the video frame and the transform skip residual coding is enabled at the slice level for the video frame, turning on sign data hiding at the slice level for the video frame.

Embodiments of the present disclosure further provide a system for performing video data processing, the system comprising: a memory storing a set of instructions; and a processor configured to execute the set of instructions to cause the system to perform: receiving a video frame for residual coding; determining whether sign data hiding is enabled at a picture level for the video frame; in response to a determination that the sign data hiding is enabled at the picture level for the video frame, turning on sign data hiding at a slice level for the video frame; determining whether sign data hiding is turned off at the slice level for the video frame; and in response to a determination that the sign data hiding is turned off at the slice level for the video frame, turning off transform skip residual coding at the slice level for the video frame.

Embodiments of the present disclosure further provide a system for performing video data processing, the system comprising: a memory storing a set of instructions; and a processor configured to execute the set of instructions to cause the system to perform: receiving a video frame for residual coding; determining whether the video frame is coded in a lossless mode at a slice level; and in response to a determination that the video frame is coded in the lossless mode at the slice level, turning off one or more loop filters at the slice level.

Embodiments of the present disclosure further provide a system for performing video data processing, the system comprising: a memory storing a set of instructions; and a processor configured to execute the set of instructions to cause the system to perform: receiving a video frame for residual coding; determining whether sign data hiding is turned off at a picture level for the video frame; in response to a determination that the sign data hiding is turned off at the picture level for the video frame, turning off transform skip residual coding at a slice level for the video frame.

Embodiments of the present disclosure further provide a system for performing video data processing, the system comprising: a memory storing a set of instructions; and a processor configured to execute the set of instructions to cause the system to perform: receiving a video frame for residual coding; determining whether a dependent quantization is enabled for the video frame; in response to a determination that the dependent quantization is enabled for the video frame, turning off transform skip residual coding at a slice level for the video frame.

Embodiments of the present disclosure further provide a non-transitory computer readable medium that stores a set of instructions that is executable by one or more processors of an apparatus to cause the apparatus to initiate a method for performing video data processing, the method comprising: receiving a video frame for residual coding; determining whether the video frame is coded according to a transform skip mode at a transform block level; and in response to a determination that the video frame is coded according to the transform skip mode, turning off sign data hiding for the residual coding.

Embodiments of the present disclosure further provide a non-transitory computer readable medium that stores a set of instructions that is executable by one or more processors of an apparatus to cause the apparatus to initiate a method for performing video data processing, the method comprising: receiving a video frame for residual coding; determining whether the video frame is coded according to a block differential pulse-code modulation mode; and in response to a determination that the video frame is coded according to the block differential pulse-code modulation code, turning off sign data hiding for the residual coding.

Embodiments of the present disclosure further provide a non-transitory computer readable medium that stores a set of instructions that is executable by one or more processors of an apparatus to cause the apparatus to initiate a method for performing video data processing, the method comprising: receiving a video frame for residual coding; determining whether the video frame is coded according to a transform skip residual coding mode at a slice level; and in response to a determination that the video frame is not coded according to the transform skip residual coding mode at the slice level, turning off sign data hiding for the residual coding.

Embodiments of the present disclosure further provide a non-transitory computer readable medium that stores a set of instructions that is executable by one or more processors of an apparatus to cause the apparatus to initiate a method for performing video data processing, the method comprising: receiving a video frame for residual coding; determining whether sign data hiding is enabled at a picture level for the video frame and whether transform skip residual coding is disabled at a slice level for the video frame; and in response to a determination that the sign data hiding is enabled at the picture level for the video frame and the transform skip residual coding is enabled at the slice level for the video frame, turning on sign data hiding at the slice level for the video frame.

Embodiments of the present disclosure further provide a non-transitory computer readable medium that stores a set of instructions that is executable by one or more processors of an apparatus to cause the apparatus to initiate a method for performing video data processing, the method comprising: receiving a video frame for residual coding; determining whether sign data hiding is enabled at a picture level for the video frame; in response to a determination that the sign data hiding is enabled at the picture level for the video frame, turning on sign data hiding at a slice level for the video frame; determining whether sign data hiding is turned off at the slice level for the video frame; and in response to a determination that the sign data hiding is turned off at the slice level for the video frame, turning off transform skip residual coding at the slice level for the video frame.

Embodiments of the present disclosure further provide a non-transitory computer readable medium that stores a set of instructions that is executable by one or more processors of an apparatus to cause the apparatus to initiate a method for performing video data processing, the method comprising: receiving a video frame for residual coding; determining whether the video frame is coded in a lossless mode at a slice level; and in response to a determination that the video frame is coded in the lossless mode at the slice level, turning off one or more loop filters at the slice level.

Embodiments of the present disclosure further provide a non-transitory computer readable medium that stores a set of instructions that is executable by one or more processors of an apparatus to cause the apparatus to initiate a method for performing video data processing, the method comprising: receiving a video frame for residual coding; determining whether sign data hiding is turned off at a picture level for the video frame; in response to a determination that the sign data hiding is turned off at the picture level for the video frame, turning off transform skip residual coding at a slice level for the video frame.

Embodiments of the present disclosure further provide a non-transitory computer readable medium that stores a set of instructions that is executable by one or more processors of an apparatus to cause the apparatus to initiate a method for performing video data processing, the method comprising: receiving a video frame for residual coding; determining whether a dependent quantization is enabled for the video frame; in response to a determination that the dependent quantization is enabled for the video frame, turning off transform skip residual coding at a slice level for the video frame.

Reference will now be made in detail to exemplary embodiments, examples of which are illustrated in the accompanying drawings. The following description refers to the accompanying drawings in which the same numbers in different drawings represent the same or similar elements unless otherwise represented. The implementations set forth in the following description of exemplary embodiments do not represent all implementations consistent with the invention. Instead, they are merely examples of apparatuses and methods consistent with aspects related to the invention as recited in the appended claims. Particular aspects of the present disclosure are described in greater detail below. The terms and definitions provided herein control, if in conflict with terms and/or definitions incorporated by reference.

The Joint Video Experts Team (JVET) of the ITU-T Video Coding Expert Group (ITU-T VCEG) and the ISO/IEC Moving Picture Expert Group (ISO/IEC MPEG) is currently developing the Versatile Video Coding (VVC/H.266) standard. The VVC standard is aimed at doubling the compression efficiency of its predecessor, the High Efficiency Video Coding (HEVC/H.265) standard. In other words, VVC's goal is to achieve the same subjective quality as HEVC/H.265 using half the bandwidth.

In order to achieve the same subjective quality as HEVC/H.265 using half the bandwidth, the Joint Video Experts Team (“JVET”) has been developing technologies beyond HEVC using the joint exploration model (“JEM”) reference software. As coding technologies were incorporated into the JEM, the JEM achieved substantially higher coding performance than HEVC. The VCEG and MPEG have also formally started the development of a next generation video compression standard beyond HEVC.

The VVC standard has been developed recently and continues to include more coding technologies that provide better compression performance. VVC is based on the same hybrid video coding system that has been used in modem video compression standards such as HEVC, H.264/AVC, MPEG2, H.263, etc.

A video is a set of static pictures (or frames) arranged in a temporal sequence to store visual information. A video capture device (e.g., a camera) can be used to capture and store those pictures in a temporal sequence, and a video playback device (e.g., a television, a computer, a smartphone, a tablet computer, a video player, or any end-user terminal with a function of display) can be used to display such pictures in the temporal sequence. Also, in some applications, a video capturing device can transmit the captured video to the video playback device (e.g., a computer with a monitor) in real-time, such as for surveillance, conferencing, or live broadcasting.

To reduce the storage space and the transmission bandwidth needed by such applications, the video can be compressed. For example, the video can be compressed before storage and transmission and decompressed before the display. The compression and decompression can be implemented by software executed by a processor (e.g., a processor of a generic computer) or specialized hardware. The module or circuitry for compression is generally referred to as an “encoder,” and the module or circuitry for decompression is generally referred to as a “decoder.” The encoder and the decoder can be collectively referred to as a “codec.” The encoder and the decoder can be implemented as any of a variety of suitable hardware, software, or a combination thereof. For example, the hardware implementation of the encoder and the decoder can include circuitry, such as one or more microprocessors, digital signal processors (“DSPs”), application-specific integrated circuits (“ASICs”), field-programmable gate arrays (“FPGAs”), discrete logic, or any combinations thereof. The software implementation of the encoder and the decoder can include program codes, computer-executable instructions, firmware, or any suitable computer-implemented algorithm or process fixed in a computer-readable medium. Video compression and decompression can be implemented by various algorithms or standards, such as MPEG-1, MPEG-2, MPEG-4, H.26x series, or the like. In some applications, the codec can decompress the video from a first coding standard and re-compress the decompressed video using a second coding standard, in which case the codec can be referred to as a “transcoder.”

The video encoding process can identify and keep useful information that can be used to reconstruct a picture. If information that was disregarded in the video encoding process cannot be fully reconstructed, the encoding process can be referred to as “lossy.” Otherwise, it can be referred to as “lossless.” Most encoding processes are lossy, which is a tradeoff to reduce the needed storage space and the transmission bandwidth.

In many cases, the useful information of a picture being encoded (referred to as a “current picture”) can include changes with respect to a reference picture (e.g., a picture previously encoded or reconstructed). Such changes can include position changes, luminosity changes, or color changes of the pixels. Position changes of a group of pixels that represent an object can reflect the motion of the object between the reference picture and the current picture.

A picture coded without referencing another picture (i.e., it is its own reference picture) is referred to as an “I-picture.” A picture is referred to as a “P-picture” if some or all blocks (e.g., blocks that generally refer to portions of the video picture) in the picture are predicted using intra prediction or inter prediction with one reference picture (e.g., uni-prediction). A picture is referred to as a “B-picture” if at least one block in it is predicted with two reference pictures (e.g., bi-prediction).

shows structures of an example video sequence, according to some embodiments of the present disclosure. As shown in, video sequencecan be a live video or a video having been captured and archived. Videocan be a real-life video, a computer-generated video (e.g., computer game video), or a combination thereof (e.g., a real-life video with augmented-reality effects). Video sequencecan be inputted from a video capture device (e.g., a camera), a video archive (e.g., a video file stored in a storage device) containing previously captured video, or a video feed interface (e.g., a video broadcast transceiver) to receive video from a video content provider.

As shown in, video sequencecan include a series of pictures arranged temporally along a timeline, including pictures,,, and. Pictures-are continuous, and there are more pictures between picturesand. In, pictureis an I-picture, the reference picture of which is pictureitself. Pictureis a P-picture, the reference picture of which is picture, as indicated by the arrow. Pictureis a B-picture, the reference pictures of which are picturesand, as indicated by the arrows. In some embodiments, the reference picture of a picture (e.g., picture) can be not immediately preceding or following the picture. For example, the reference picture of picturecan be a picture preceding picture. It should be noted that the reference pictures of pictures-are only examples, and the present disclosure does not limit embodiments of the reference pictures as the examples shown in.

Typically, video codecs do not encode or decode an entire picture at one time due to the computing complexity of such tasks. Rather, they can split the picture into basic segments, and encode or decode the picture segment by segment. Such basic segments are referred to as basic processing units (“BPUs”) in the present disclosure. For example, structureinshows an example structure of a picture of video sequence(e.g., any of pictures-). In structure, a picture is divided into 4×4 basic processing units, the boundaries of which are shown as dash lines. In some embodiments, the basic processing units can be referred to as “macroblocks” in some video coding standards (e.g., MPEG family, H.261, H.263, or H.264/AVC), or as “coding tree units” (“CTUs”) in some other video coding standards (e.g., H.265/HEVC or H.266/VVC). The basic processing units can have variable sizes in a picture, such as 128×128, 64×64, 32×32, 16×16, 4×8, 16×32, or any arbitrary shape and size of pixels. The sizes and shapes of the basic processing units can be selected for a picture based on the balance of coding efficiency and levels of details to be kept in the basic processing unit.

The basic processing units can be logical units, which can include a group of different types of video data stored in a computer memory (e.g., in a video frame buffer). For example, a basic processing unit of a color picture can include a luma component (Y) representing achromatic brightness information, one or more chroma components (e.g., Cb and Cr) representing color information, and associated syntax elements, in which the luma and chroma components can have the same size of the basic processing unit. The luma and chroma components can be referred to as “coding tree blocks” (“CTBs”) in some video coding standards (e.g., H.265/HEVC or H.266/VVC). Any operation performed to a basic processing unit can be repeatedly performed to each of its luma and chroma components.

Video coding has multiple stages of operations, examples of which are shown inand. For each stage, the size of the basic processing units can still be too large for processing, and thus can be further divided into segments referred to as “basic processing sub-units” in the present disclosure. In some embodiments, the basic processing sub-units can be referred to as “blocks” in some video coding standards (e.g., MPEG family, H.261, H.263, or H.264/AVC), or as “coding units” (“CUs”) in some other video coding standards (e.g., H.265/HEVC or H.266/VVC). A basic processing sub-unit can have the same or smaller size than the basic processing unit. Similar to the basic processing units, basic processing sub-units are also logical units, which can include a group of different types of video data (e.g., Y, Cb, Cr, and associated syntax elements) stored in a computer memory (e.g., in a video frame buffer). Any operation performed to a basic processing sub-unit can be repeatedly performed to each of its luma and chroma components. It should be noted that such division can be performed to further levels depending on processing needs. It should also be noted that different stages can divide the basic processing units using different schemes.

For example, at a mode decision stage (an example of which is shown in), the encoder can decide what prediction mode (e.g., intra-picture prediction or inter-picture prediction) to use for a basic processing unit, which can be too large to make such a decision. The encoder can split the basic processing unit into multiple basic processing sub-units (e.g., CUs as in H.265/HEVC or H.266/VVC), and decide a prediction type for each individual basic processing sub-unit.

For another example, at a prediction stage (an example of which is shown in), the encoder can perform prediction operation at the level of basic processing sub-units (e.g., CUs). However, in some cases, a basic processing sub-unit can still be too large to process. The encoder can further split the basic processing sub-unit into smaller segments (e.g., referred to as “prediction blocks” or “PBs” in H.265/HEVC or H.266/VVC), at the level of which the prediction operation can be performed.

For another example, at a transform stage (an example of which is shown in), the encoder can perform a transform operation for residual basic processing sub-units (e.g., CUs). However, in some cases, a basic processing sub-unit can still be too large to process. The encoder can further split the basic processing sub-unit into smaller segments (e.g., referred to as “transform blocks” or “TBs” in H.265/HEVC or H.266/VVC), at the level of which the transform operation can be performed. It should be noted that the division schemes of the same basic processing sub-unit can be different at the prediction stage and the transform stage. For example, in H.265/HEVC or H.266/VVC, the prediction blocks and transform blocks of the same CU can have different sizes and numbers.

In structureof, basic processing unitis further divided into 3×3 basic processing sub-units, the boundaries of which are shown as dotted lines. Different basic processing units of the same picture can be divided into basic processing sub-units in different schemes.

In some implementations, to provide the capability of parallel processing and error resilience to video encoding and decoding, a picture can be divided into regions for processing, such that, for a region of the picture, the encoding or decoding process can depend on no information from any other region of the picture. In other words, each region of the picture can be processed independently. By doing so, the codec can process different regions of a picture in parallel, thus increasing the coding efficiency. Also, when data of a region is corrupted in the processing or lost in network transmission, the codec can correctly encode or decode other regions of the same picture without reliance on the corrupted or lost data, thus providing the capability of error resilience. In some video coding standards, a picture can be divided into different types of regions. For example, H.265/HEVC and H.266/VVC provide two types of regions: “slices” and “tiles.” It should also be noted that different pictures of video sequencecan have different partition schemes for dividing a picture into regions.

For example, in, structureis divided into three regions,, and, the boundaries of which are shown as solid lines inside structure. Regionincludes four basic processing units. Each of regionsandincludes six basic processing units. It should be noted that the basic processing units, basic processing sub-units, and regions of structureinare only examples, and the present disclosure does not limit embodiments thereof.

shows a schematic of an example encoding process, according to some embodiments of the present disclosure. For example, encoding processA shown incan be performed by an encoder. As shown in, the encoder can encode video sequenceinto video bitstreamaccording to processA. Similar to video sequencein, video sequencecan include a set of pictures (referred to as “original pictures”) arranged in a temporal order. Similar to structurein, each original picture of video sequencecan be divided by the encoder into basic processing units, basic processing sub-units, or regions for processing. In some embodiments, the encoder can perform processA at the level of basic processing units for each original picture of video sequence. For example, the encoder can perform processA in an iterative manner, in which the encoder can encode a basic processing unit in one iteration of processA. In some embodiments, the encoder can perform processA in parallel for regions (e.g., regions-) of each original picture of video sequence.

In, the encoder can feed a basic processing unit (referred to as an “original BPU”) of an original picture of video sequenceto prediction stageto generate prediction dataand predicted BPU. The encoder can subtract predicted BPUfrom the original BPU to generate residual BPU. The encoder can feed residual BPUto transform stageand quantization stageto generate quantized transform coefficients. The encoder can feed prediction dataand quantized transform coefficientsto binary coding stageto generate video bitstream. Components,,,,,,,,, andcan be referred to as a “forward path.” During processA, after quantization stage, the encoder can feed quantized transform coefficientsto inverse quantization stageand inverse transform stageto generate reconstructed residual BPU. The encoder can add reconstructed residual BPUto predicted BPUto generate prediction reference, which is used in prediction stagefor the next iteration of processA. Components,,, andof processA can be referred to as a “reconstruction path.” The reconstruction path can be used to ensure that both the encoder and the decoder use the same reference data for prediction.

The encoder can perform processA iteratively to encode each original BPU of the original picture (in the forward path) and generate predicted referencefor encoding the next original BPU of the original picture (in the reconstruction path). After encoding all original BPUs of the original picture, the encoder can proceed to encode the next picture in video sequence.